War, disease, and natural destructive forces (mainly fire) caused the populations of major U.S. cities to temporarily swell and dip throughout American history. The Great Yellow Fever Epidemic of 1793 in Philadelphia, for example, caused the deaths of 5,000 inhabitants and inspired an additional 17,000 to flee the city limits, dramatically reducing the city population from 40,000 to 18,000 - a 55% decrease. Additionally, a score of cities throughout the Civil War - particularly in the South, i.e. Richmond, Atlanta, Charleston - were either evacuated or destroyed, or both. But when populations dipped due to war, disease, or natural destructive forces, commerce and industry oftentimes quickly rebounded after, and population size swelled back to normal. Think Chicago in 1871 or San Francisco in 1906.

But what we're seeing in Detroit is something else entirely, an epidemic of industry, and one that does not show many promising signs of rebounding. In terms of scale, Detroit is undoubtably the largest American city to experience the type of continual decline that we're seeing now. Remember, it's also the largest urban municipality to officially declare bankruptcy in U.S. History.

Nevertheless, there are examples of smaller cities, mainly industrial cities not unlike Detroit, which have experienced similar tragic dips in population and economy. Cairo, Illinois is a good example of a city that fell due to a similar commercial collapse. Founded by railroad and canal entrepreneurs in the mid-19th century, Cairo was situated on a promising geographically cleavage point between the Mississippi and Ohio rivers. Despite frequent flooding, steamboat and railroad commerce was healthy and the population of Cairo blossomed with the peak population hitting 20,000 in 1907. Today, however, Cairo boasts a population of only 2,660 people, an 86% decrease (comparatively, the percent decrease of Detroit's population is closer to 62%) Cairo collapsed because changes in river industry and transportation negated the geographical importance of it's location, while a string of bridges and highways forced industry to bypass the city. Joblessness, racial tensions, and an emaciated municipal budget followed. What base economy can Cairo hope to spur growth now? Tourism? Free land schemes? The future of places like Cairo or Detroit is obviously uncertain, but the prognosis cannot be good.

Sources: Howard Chudacoff and Peter C. Baldwin," Major Problems in American Urban and Suburban History," and "The Endless Sufferings of Cairo, Illinois" by Dave Albin, article. Population statistics mostly came from City-Data.com

They aren't quite on the same scale as Detroit but Virginia City Nevada and Goldfield Nevada both experienced huge population losses. Goldfield went from 20,000 people in 1906 to 4,800 in 1910 to about 500 in 1923 when a fire destroyed most of the buildings in the town. Today there are only 268 people in the town. Virginia city experienced a similar but slower decline from 15,000 in 1863 to about 600 in 1930. In terms of percentage these "cities" declined much further than Detroit.

In 1978 the Khmer Rouge forcefully depopulated Phnom Penh to a population of about 32,000. Today there are approximately 2,200,000 people in the city.

These examples have radically different causes than Detroit they do show that some cities recover and some don't. But because they are so different from Detroit they don't give a good indication of what will happen to Detroit.

Cairo Illinois.

Its a city located almost exactly at the southern tip of Illinois where the Mississippi meets the Ohio. In the late 1800's and early 1900's it was a booming shipping center with over 15,000 residents. In the middle of the 1900's the shipping dried up though and many of the jobs disappeared. The area was also rocked by a lot of racial violence throughout the early and mid 1900's.

Today the city has a population of less than 3,000, its extremely poor, and has several beautiful historical buildings that are surrounded by urban decay.